Placer-mining machine



Aug. 9, 1932. w. G. CHURCHILL PIACER MINING MACHINE original Filed May 1, 192s 2 Sheets-Sheet l L@ Q Q Q w @Sm INI/EN TOR. #fama/zb TORNE Y.

Aug'. 9, 1932.,

W. G. CHURCHILL PLACER MINING MACHINE 2 Sheets-Sheet 2 Original Filed May l, 1928 INI/ENTOR ATTORNEY.

Patented Aug. 9, 1932 PATEN WINSTON G. CHURCHILL, OF DENVER, COLORADO; ADELAIDE IiAlVIB CHURCHILL `EXEC- UTRIX vOF' SAID WINSTON VGr. CHURCHILL, DECIEIASED PLACER-MINING- MACHINE Applicaton ledMay 1, 1928, Serial No. 274,225. Renewed December 3, 1931. f

My invention relates to separators, and its primary object is to provide a mechanism of simple construction which in its operation separates metals from their gangues by magnetic influence and centrifugal force.

The invention is particularly adapted for the recovery of gold from black sand in placer mining, and it is in this connection that it will hereinafter be described. y

The invention, however, is not limited to the separation of gold from black sand, since another object is to separate non-magnetic from magnetic matter. y

A still further object is to `combine the two Vfields of separation, to-wit, centrifugal force and magnetism. Y

Other obj ects reside principally in details of construction and in novel arrangements and combinations of parts.

In the drawings, in which like parts are similarly designated throughout the several views,

c Figure 1 is an elevation, partly in section, of a machine embodying the present invention; v

Figure 2 is a section taken on the line 2-2 of Figure 1;

Figure 3 is an enlarged section taken on the line 33, Figure 2;

Figure 4 is a still further enlarged sectional view of a. portion of one of the separating bowls included in the present invention; Y y t Figure 5 is an enlarged sectional view of a distributing chamber used in the present invention; and

Figure 6 is a section taken on the line 6-6 of Figure 5.

Referring more specifically to the drawings, the separator is mounted upon a truck chassis designated generally by the reference numeral 5. The details of the truckv are-not a part of the present invention, so shall not be minutely described. ,s

The truck has a driving shaft which connects the motor of the truck with the driving wheels 7. The shaft is made in two Asections 6 and 8 which are connected by a sleeve 9 and bolts 10. When the separator isto be operated, the'motorV of the truck is disconwheel 13 for the operation ofthe separator.

Mounted on the truck is a supporting frame 57 carrying a tilted pan 14 for receiving waste matter from separating bowls 15 suspended in the pan, as will be more fully explained hereinafter. i

Mounted on standards 16 on the frame 57 is a tilted'screening unit comprising-a housing 17 and concentric rotating screens 18 and 19 within the housing. The inner screen 18 is coarser than the outer one 19 and is held in spaced relation thereto by spiders 20.

Roller bearings 22 on the inner surface of the drum support the rotating screens 18 and 19 by means of tread rings24 on the circumference of the outer screen 19. A circular rack 25 Valso on the outer screen engages with a driving pinion 26 on a shaft 27. v

The shaft 27 is driven by an angularly arranged stub shaft 29 through the medium of a universal joint 28. The sprocket 13 on the driving shaft of the truck drives one of two sprockets 31 and 32 on a jack shaft 33 through the medium of a chain 34. IThe other sprock- .et 32 drives 'a sprocket 30 on the stubshaft 29 by a chain 35.

A hopper 36 has a spout 37 that feeds material into the coarse screen 18. An endless belt 38 is provided to'feed the material into the hopper 36. Onlythe end of the belt adjacent the hopper is shown, the remainder being of conventional design.k t

A transverse `shaft 39 is driven from the jack shaft 33 by bevel gears 40 and 41. The transverse shaft 39 carries a sprocket 42 that drives a chain 43 which in turnoperates the endless belt 38 through the medium of a sprocket 44.

Apump 45 on the truck iso-perated by the chain 34. The pump feeds waterto the hope per 36 by apipe 46 and to thescreens by a lso pipe 47 having a perforated portion 48 with-l in the inner screen 18.

A chute 49 receives coarse material from the linterior of the screens and discharges it into a drain spout 50 on the pan 14.

The separating bowls 15 are *arranged in .two rows in the pan. rlherows are separa-ted by a lengthwise partition 66, and the bowls in each row are separatediby transverse partitions 77. The transverse partitionsy are spaced from the bottom of the pan to provide passageways 78 for material to the spout 50 at the end of the pan.

The bottom of the housing 17 slopes'to a substantially central outlet 51. rl`he outlet is connected with the separating bowls' 15 by pipes 52 radiating from the outlet.V- A cone 53 in the outlet divides the material among the pipes. Y s

` A valve' 54 in each pipe controls the flow of material to -the bowls 15.

Parallel line shafts 55 mounted on the frame 57 are driven by the transverse shaft 39 through the intermediary of bevel gears 56. Cross bars 82 are provided between the side channels of the frame 57 for the suspension of shafts 58 that carry the separating bowls 15. The bowls are fastened to the shafts 58 and rotate therewith. Each of the shafts carries a bevel gear 80 at its upper end, which engages with-bevel gears 81 on the line shafts 55. The cross bars 82 have bearings 84 for the suspension shafts.

The bowls 15 are vof substantially hemispherical form and have at their inner surfaces, a series of circumferential riffles 59, each provided with a pointed end-portion 60 of different material. Rearward of said endportions and beneath each riffle is an annular pocket provided with a recess 61 in its under side. The outer surfaces 62 of the riliies slope Vdownward from the pockets of those immediately above the same with the exception of the uppermost riflie whose surface slopesfrom the rim of the bowl. Y

The body portions of the riiiies are integral with the wall of the bowl which is composed of non-magnetic and preferably conductive material in contrast with the tipsV 60 of the rii'lles which are made of a magnetic sub stance. It will be understood, however, that a bowl composed of non-conducting material may be substituted without appreciable modilication, and further without departing from the scope and spirit of the invention. I

The bowl carries upon its outer surface a number of electro1nagnets64 connected byy a conductive railzor contact-strip 63 extending part of the way around the bowl,the entire structure being held in place by insulated bolts and so arranged asto effect a suitable balancingof the bowl during its rotation.

Bearing against the contact strip is a brush 65 in an electrical circuit. The brushes are supported by andlinsu-lated from the partition 66. A wire 87, leading from the brush 65, connects with a source of electric energy 88, which is grounded on the frame of the truck by a ground wire 89.

The pipes 52 discharge into the bowls preferably almost-at the bottoms thereof. The

Vpipes may be concentric with the shafts. If

concentric, the shaft may extend through an opening 69 in the upper part of the pipe, as shown in Figure 3. i e Each Iof the bowls has an outlet 70 normally closed vby a screw plug 71. Scrapers 72 in the bowls prevent foreign matter from clogging the pockets. The scrapers have a serrated edge 7 3 conforming to the riftles on the interior of the bowl. The scrapers are suspended from the cross bars by rods174,

and may be made adjustable on the rods by a bolt 75 in an elongated eye 76 in the bar.

Doors 79 are provided on either side of the pan to make the bowls readily accessible from the exterior of the pan. l

In operation, the material under treatment, preferably sand or gravel found in placer mining, is conveyed to the hopper 36 by the carrier belt 38. The pumpV 45 supplies water to the rhopper to miX with the material. v

The wet material is fed'into the inner and coarser screen where itis subjected to a washing action by sprays of water from the perforated pipe 48. The water and rotation of the screens scour and wash the material to separate all ne material from the coarse and to wash gold-bearing black sand from the coarse material as much as possible.

The line material passes through both screens and to the outlet 51 of the housing. The coarser materialvin both screens passes into the chute 49 and is carried away by the waste water throughvthe spout 50.` r

The fine material finding its way to -the outlet 51 is divided and fed through the pipes Y vehicle frame constituting the ground and the conductor 89 connecting the ground with the source of electricity. Y Y

'The solids in the aqueous mass in each bowl Vare moved by centrifugal force to engagement with the'circumferential wall of the bowl. The magnetic blacksand, attracted by the magnetizedtips vof the riliies, remains there-while the non-magnetic matter is' carried away.

The-water, likewise moved by centrifugal i" force, washes the non-magnetic gold from the black sand on the magnetized riiile-tips into the pockets 6l.

The above operation takes place only while the electromagnets are in the circuit, and, when the contact strip disengages the respective brush, the black sand is released from the rifies and moves onto the next ones, where the above operation is repeated.

The material that is being fed into the bottom of the bowl washes the black sand up to the riiiies above.

Each time the points attract the black sand, it will be held in a different position, so that all of the gold may be recovered from the material before it is washed over the top of the bowl by the waste water. The sera-pers prevent the pockets from clogging with foreign matter.

The waste matter flows under the cross partitions through the passage-ways 78 and out through the spout 50, carrying the coarse matter from the screens.

At the end of the operation, the bowls are drained through the outlets by removing the screw plugs. The free iiour gold, which has caked in the pockets by the centrifugal force, may then be removed.

The motor of the truck is used to operate the separator through the clutch 12 by disconnecting the motor shaft from the driving wheels by removing one of the bolts 10. When it is desired to continue the operation at a different location, the clutch is moved by the operating lever to disconnect the separator from the drive shaft, and the bolt l0 is replaced.

Vhat I claim:

l. In a separator, a rotary, non-inagnetic bowl having interiorly, circumferential magnectic rifies, and having back of the magnetic riffles pockets to receive values washed from material held on the riliies by magnetic force, and means for magnetization of the riflles during rotation of the bowl.

2. In a separator, a rotary, non-magnetic bowl having interiorly, circumferential magnetic riflies and having back of the magnetic riiiies pockets to receive values washed from material held on the riflles by magnetic force, and means for intermittentmagnetization of the riifles during rotation of the bowl.

3. In a separator, a rotary, non-magnetic bowl having interiorly, circumferential riifles 5 terminating in magnetic tips, and having the riiiesfby magnetic force, and means for magnetization of the riles during rotation of the bowl. Y

5. In a separator, a rotary, non-magnetic bowl having interiorly, circumferential magnetic riftles and having back ofthe magnetic riiiies, pockets formedby recesses in the under surface of the riilies'rearward of the tips, to receive. values washed from material held on the riifles by magnetic force, and mean-s for magnetization-of the riiiles during rota-- tion of thebowl.

6. In a separator, a rotary, non-magnetic bowl having interiorly, circumferential magnetic riiiles and having back of the magnetic riffles, pockets to receive values washed from material held on the riiiies by magnetic. force, anl electric circuit, a brush in the circuit, a magnet on the bowl for magnetizing the riftles, and a contact strip in electric connection with the magnets, the Contact strip being vso disposed to engage the brush during a portion of the rotation of the bowl.

7. In a separator, a rotary, non-magnetic bowl having interiorly, circumferential magnetic riffles and having back of the magnetic riffles, pockets to receive values washed from material held onthe rilles by magnetic force, an electric circuit, a brush in the circuit, a magnet on the bowl for magnetizing the rimes, and a contact strip extending partially around the bowl and in electric connection with the magnets, the contact strip being disposed to engage the brush during a portion of the rotation of the bowl.

8. In a separator, a rotary, non-'magnetic bowl having interiorly, circumferential magnetic riffles and having back of the magnetic riflies, pockets to receive values washed from material held on the riiiles by magnetic force, means for magnetization of the riiiies during rotation of the bowl, and a scraper in the bowl to prevent foreign matter from clogging the rifies.

9. A separator comprising a rotary container, riiiies in the container having magnetic portions, means to magnetize the portions including an electro-magnet and a circuit for the magnet includingmeans to close the circuit during a portion ofthe rotation of the container.

l0. A separator comprising a rotary bowl for containing an aqueous mass of material under treatment and having a magnetizable element rotating therewith for the retention of magnetizable values of the material, mechanism for rotating the bowl, means for magnetizing the elementiduring rotation of the under treatment and having a magnetizable V element rotating therewith forthe retention of magnetizable values in the material, the

bowl having means therein adjacent said element to catch the non-magnetizable material impelled by centrifugal force.

12. A. separator comprising a rotary bowl for containing an aqueous mass of material under treatment and having a magnetizable element rotating therewith for the retention of magnetizable values in the material, meehanism for rotating the bowl, means for mag- Y netizing intermittently the elementv during rotation of the bowl, the bowl having means adjacent the element for vcatching the nonmagnetizable material impelled by centrifugal force.

In testimony whereof I have aHiXed my signature. t WINSTON Gn CHURCHILL. 

